1. Field of the Invention
The present disclosure relates to a vehicle mounted apparatus for use in high-pressure fluid blasting, and in particular, to an apparatus that is suitable for mounting onto a truck for removing material from a road, airport runway, or other paved surface. The apparatus is particularly suitable for removing bitumen.
2. Discussion of the Background Art
High-pressure fluid blasting systems, and in particular water blasting systems, are used in a variety of situations for cleaning or otherwise treating surfaces. The treatment may be a conditioning treatment, in which material, such as tar bleed, is removed from the upper surface of a road or other paved surface so as to recondition the surface in order to extend the safe useable lifetime of the surface. Surface treatment may also involve the removal of painted road markings and lines or may involve the more radical cutting or removal of material for example in order to re-lay the surface.
The roading systems of many countries, including Australia and New Zealand, use chip sealing to provide waterproof, flexible and reliable road surfaces for wheeled vehicles. Chip sealing is a method of sealing a road in which a layer of bitumen based binder is applied to the road bed followed by a layer of stone chips. The surface of the road is then rolled to embed the stone chips into the binder. Chip sealed roads can require resurfacing for a multitude of reasons. For example, ‘flushing’ describes the smooth surface of a road caused by excess binder rising to the surface. This can occur as a result of the stone chips being forced into a soft substrate under the wheels of vehicles. The occurrence of flushing has to be immediately rectified to ensure optimal road surface texture and to maintain vehicle safety.
In order to repair the surface of a road that has undergone flushing, it is known to use high-pressure water blasters to remove the bitumen based binder from the road so that the road can be resealed. Bitumen is an extremely adhesive material which in its stabilised form is highly viscous and almost solid. In a chip sealed road, the uppermost bitumen is toughened and the underlying bitumen remains in a viscous state. After being released from the road, the freed bitumen particles retain their full adhesion properties. The exceptional adhesion properties of bitumen combined with its high or low viscosity create significant difficulties for transporting the material through enclosed mediums for storage in a holding tank without residue or blockage occurring.
At least two different water blasting arrangements are known. The most common arrangement involves a high-pressure/high-volume water blasting arrangement. However, such arrangements have proven to be unreliable, especially in the area of surface reconditioning and tar bleed removal and suffer a significant disadvantage in that very high volumes of waste water and wetted waste material removed from the road surface need to be disposed of. Because of contamination of the treatment water, the water and removed material must be removed from the treatment site and disposed of in a sanctioned waste area. The removal of such large amounts of waste material and contaminated water has, until now, involved the use of very large vacuum devices operating with internal storage capacity or separate disposal trucks. As these trucks must frequently visit an approved disposal site, the equipment is prone to long downtimes. In addition, when treating roads in remote areas, large volumes of water may not be immediately available and the transportation of large volumes of water significantly increases operational costs.
An alternative approach to road and pavement surface treatment has been developed by the applicant and involves the use of ultra high-pressure/low-volume fluid blasting. This fluid blasting unit operates at pressures in the region of 40,000 psi (2,800 bar) but with flow rates as low as 3.5 to 4.5 liters/min. However, even with significantly reduced flows, the UHP/LV system still requires the safe and environmentally acceptable removal of waste products.
It is an object of the present disclosure to provide a vehicle mounted apparatus that at least mitigates some of the problems associated with the prior art.